Help! How do I refill coolant?

[belfert]

I ended up draining all of the coolant out of my Series 60 after I lost 5 gallons removing the baseboard heat inside the coach.  I have replacement coolant and distilled water.

My concern is getting the coolant back in.  I'm certain I won't be able to just dump in 20 gallons of coolant at once, but I don't really want to start the engine without enough coolant either.  How do I make sure all the trapped air gets out of the system?  I suppose I should check my maintainance manual.

Brian Elfert

[JackConrad]

There should be a few petcocks at the "high spots" such ar the driver's heat/defroster to allow the air to bleed out. Best bet is check you manual for the location of these. Another thing that can help is fill the system, walk away, check it later, add coolant, walk away, check it, add coolant, etc, until you can add no more. Then start engine and check level as engine warms up. YMMV. Hope this helps, Jack

[belfert]

There don't appear to be appear to be any petcocks in the heating loop.  The manual says to remove a hose from the defrost core when draining coolant.  That certainly won't help for replacing the coolant.  There don't appear to be any instructions in the manual for replacing the coolant.

It doesn't look like I will get the coolant done tonight as it is starting to pour rain outside.

Brian Elfert

[DrivingMissLazy]

I had to loosen a hose on the defroster with the engine running until coolant came out the hose or the defroster unit. Whichever was on the pressure side. Once you fill the radiator , you can run the engine a few minutes to start circulating fluid. Then shut down and refill the radiator. Keep up this cycle until you can add no more fluid. Then start on the defroster part of the operation. Do not run the engine more that 2-3 minutes at a time  at first until you are sure you are getting water up thru the heads.
Richard

There don't appear to be appear to be any petcocks in the heating loop.  The manual says to remove a hose from the defrost core when draining coolant.  That certainly won't help for replacing the coolant.  There don't appear to be any instructions in the manual for replacing the coolant.

It doesn't look like I will get the coolant done tonight as it is starting to pour rain outside.

Brian Elfert

[belfert]

I had to loosen a hose on the defroster with the engine running until coolant came out the hose or the defroster unit. Whichever was on the pressure side. Once you fill the radiator , you can run the engine a few minutes to start circulating fluid. Then shut down and refill the radiator. Keep up this cycle until you can add no more fluid. Then start on the defroster part of the operation. Do not run the engine more that 2-3 minutes at a time  at first until you are sure you are getting water up thru the heads.

I think I am going to have to get my mechanic friend over again.  I can't get the hose off the defroster and I know he knows all the tricks.  He can also help with draining the engine.

Brian Elfert

[Sammy]

Fill the cooling system, start engine, add some more coolant,now run the engine until the thermostats open.
You will have to drive the bus to get the coolant temp hot enough to open the thermostats.
Check the thermostat housing - some have a small petcock on them to bleed air from system.
Don't go very far, it won't be necessary - stay local.
Just need to put a normal load (regular driving) on the engine to let it heat up.Watch the temp guage, at about 180 the t-stats will open(depends on what t-stats you have).
Take some coolant with you on your road test - about 5 gals.
The coolant level in the surge tank will drop when the t-stats open,
DDEC might shut down the engine because it detects a "low coolant level" - depends on how your engine protection parameter is set.
Be careful when you open the surge tank to fill the coolant at this time 
Coolant is now hot and there will be pressure to be released before you open the surge tank cap.
Fill your coolant to the proper final level, run bus again, final check coolant level.
Hope this helps.Good luck with your repair.
Sammy 

[Busted Knuckle]

As always Sammy is 100% on the mark with the way I'd go about it! BK